Heartbleed is a devastating bug that shatters online encryption efforts

No matter how hard you try to stay safe, some aspects of securing your online data are completely out of your hands. That fact was made painfully obvious on Monday, when the Internet got caught with its collective pants down thanks to a critical vulnerability affecting a fundamental tool for secure online communications.

Called Heartbleed, the bug has been in the wild for more than two years now. It allows attackers to exploit a critical programming flaw in OpenSSL--an open source implementation of the SSL/TLS encryption protocol.

When exploited, the flaw leaks data from a server's memory, which could include SSL site keys, usernames and passwords, and even personal user data such as email, instant messages, and files, according to Finland-based Codenomicon, the security firm that first uncovered Heartbleed in concert with a Google researcher.

That's bad. Real bad, though it's important to note that Heartbleed only affects OpenSSL and not the security protocol itself.

But due to OpenSSL's popularity with website administrators, the potential number of affected websites is huge. Security and Internet research firm Netcraft estimates that Heartbleed affects around half a million "widely trusted websites."

Yahoo has already said it was hit by the Heartbleed bug and Yahoo-owned Tumblr is advising users to update their passwords ASAP.

"On the scale of 1 to 10, this [Heartbleed] is an 11," respected security expert Bruce Schneier said on his blog.

Yes, this bug is pretty serious and almost certainly affects at least one of your online accounts. But now that we've got the scary stuff out of the way, let's talk about some of the practical measures you need to know about.

Keep calm and...

Thanks to Hearbleed it's possible that some unscrupulous actors online could have your username and password. And you should definitely change your password on any site that says it was affected.

But here's the thing: While OpenSSL already has a fix available, changing your username and password before a site patches its servers achieves nothing. In fact, it could make things worse.

"You should change password after the service provider has patched their site. Otherwise you just contribute to the data that can be stolen," Codenomicon spokesperson Ari Takanen told us via email.

...don't carry on

Heartbleed was publicized on Monday. So by now, many sites should have scrambled (or are scrambling) to patch their servers. You can find out if a site is still affected by Heartbleed using online checkers provided by LastPass, Qualsys, or Filippo Valsorda.

If you find that a site you use often is still affected by the vulnerability, Codenomicon advises to take a "day off" from that site. Heartbleed only exposes data that's held in a server's memory (RAM). This isn't a break-in and read the database type flaw. Your data needs to be in a server's memory when it's attacked to be exposed.

That's one reason why changing your password before a site is patched could actually be worse than doing nothing, especially now that Heartbleed is public knowledge.

Other considerations

Security flaws like this are also a good time for some reminders about how best to secure your online accounts.

You should really be using two-factor authentication for all your accounts that offer it. Two-factor authentication requires you to enter an extra code before accessing your online accounts. The code is typically generated by a smartphone app or keychain dongle, but you can also receive codes to your phone via SMS.

This extra step requires attackers to know how to generate your two-factor authentication code before they can login to your account. In the case of Heartbleed, two-factor authentication may not have been as useful a defense, but in general this extra step helps keep your account safer than it was.

Use a password manager

Now's a good time to start using a password manager especially if you're going to be changing some user logins over the next few days. A password manager makes it easy to generate randomized passwords using a combination of letters, numbers, and special characters. It also relieves you of having to memorize every one of those overly complex codes.

Password managers often come with other features as well such as secure notes, and autofill for online forms.

There are many options out there for password managers, but some of our favorites include LastPass, Dashlane, and KeePass. LastPass recently said in a blog post that it was using the version of OpenSSL affected by Heartbleed; however, because the service encrypts your data before transmitting it online, the company says its users were not at risk of having their data exposed to the bad guys.

Heartbleed is certainly a nasty little bug that needs to be taken seriously. But considering it's been in the wild for more than two years, there's not much a user can do now except wait patiently for affected sites to patch their servers before changing any passwords.

Once those sites are patched, however, you'll want to change your password as soon as possible.

This story, "The critical, widespread Heartbleed bug and you: How to keep your private info safe" was originally published by
PCWorld.

Ian is an independent writer based in Tel Aviv, Israel. His current focus is on all things tech including mobile devices, desktop and laptop computers, software, social networks, Web apps, tech-related legislation and corporate tech news.